Motor fuel multipurpose agents



United States Patent 3,551,461 MOTOR FUEL MULTIPURPOSE AGENTS Helen I. Thayer, Oakrnont, Pa., assignor to Gulf Research & Development Company, Pittsburgh, Pa., a corporation of Delaware N0 Drawing. Original application Apr. 25, 1966, Ser. No. 544,840, now Patent No. 3,497,333, dated Feb. 24, 1970. Divided and this application Aug. v19, 1968, Ser.

Int. Cl. A23j 7/00 US. Cl. 260-403 4 Claims ABSTRACT OF THE DISCLOSURE This application is a division of Serial Number 544,840 filed Apr. 25, 1966 now Pat. No. 3,497,333.

This invention relates to multipurpose additives for motor fuels, to motor fuel compositions containing a minor proportion of said additives, and to methods for improving operation of gasoline burning engines by utilizing said compositions. The gasoline additives of the present invention perform three primary functions in gasoline including (1) reducing wear of cast iron piston rings in a gasoline-burning engine, (2) reducing the tendency of gasoline to clog a fuel filter element, and (3) performing a carburetor gum detergency function to inhibit or remove carburetor-type gum formations.

The additives of the present invention comprise monoethoxylated or monopropoxylated derivatives of di alkylene triamines or trialkylene tetramines and lecithin mixtures with and derivatives of said triamines or tetramines. A preferred gasoline additive of the present invention is monoethoxylated dipropylene triamine having the formula and the lecithin derivative thereof. Brackets are utilized in the structural formula to signify that the propylene can be either a l-methylethylene or a Z-methylethylene substituent.

In the absence of lecithin, the alkoxylated triamines or tetramines of this invention impart antiwear characteristics to gasoline as evidenced by reduction in loss of metallic iron from cast iron piston rings. However, lecithin mixtures with and lecithin derivatives of the alkoxylated triamines or tetramines of this invention exert an additional highly beneficial effect in gasoline, i.e., they reduce the tendency of the gasoline to clog the fuel filter through which it passes in its flow to an engine. In addition, the lecithin derivatives perform a carburetor detergency function by inhibiting or reducing formation of gummy carburetor deposits. It is shown below that the derivative of lecithin and an alkoxylated triamine of this invention far excelled a large number of closely related compounds in ability to inhibit or reduce formation of gummy carburetor-type deposits.

The observed reduction in fuel filter clogging with the lecithin-containing additives of this invention signifies that these additives cause dispersed solids in gasoline to be either completely dissolved or partially dissolved and reduced in size. This indicates that the antiwear and antifilter-clogging characteristics of the additives of this invention cooperate to reduce engine Wear because the presence of solid particles in gasoline, especially relatively large particles, in itself tends to increase wear of piston rings by abrasion. The antiwear and antifilter-clogging characteristics of the additives of this invention therefore cooperate to reduce engine Wear with the antiwear function contributing directly to piston ring wear rate reduction and the antifilter-clogging function contributing indirectly to reduction of engine wear by completely dissolving or partially dissolving and reducing the size of abrasive solid particles in gasoline, thereby permitting easier removal by filtration of any remaining relatively small but still potentially abrasive solids.

It is significant that compounds differing only slightly from the additives of the present invention do not exhibit the advantageous characteristics in gasoline of the compounds of this invention. For example, While lecithin with monoethoxylated dipropylene triamine having the formula J CH3 is a highly advantageous compound of the present invention, it is shown below that lecithin with dipropylene triamine plus two mols of ethylene oxide having the formula The triamine and tetramine compounds of the present invention have the general formula group, R is a C H OH or -C H OH group, and n is 1 or 2.

Examples of amine compounds of this invention include the monoethoxylate and monopropoxylate of diethylene triamine, dipropylene triamine, ditrimethylene triamine, triethylene tetramine, tripropylene tetramine, N-aminomethylethylenediamine, N-aminoethyl-N-aminopropyltrimethylene diamine, N-methyltripropylene tetramine and N-methylaminoethyldiethylene triamine.

Any lecithin can .be utilized in accordance with this invention, such as lecithin derived from soybean oil, corn oil, egg yolk or linseed oil. A suitable commercial lecithin to be reacted with an ethoxylated or propoxylated triamine or tetramine compound of this invention is a neutral oil solution of a filtered soybean lecithin with a moisture value less than 0.75 percent, an acetone-insoluble value of 70 percent and a viscosity of 3046 centipoises. According to one method of preparation of the lecithin derivative of the ethoxylated or propoxylated triamine or tetramine, base lecithin is reacted with the triamine or tetramine at 5580 C. for 19 to 55 hours while stirring the reaction mixture. The reaction conditions of the base lecithin with the ethoxylated or propoxylated triamine or tetramine of this invention are not critical. In general, the reaction can occur at a temperature between 40 and 100 C. for a time duration of 5 to 100 hours.

The concentration in gasoline of the additives of this invention is not critical. For example, the additives of this invention can be present in gasoline in a general concentration range of 0.1 to 100 pounds per 1000 barrels, or a preferable concentration range of 1 to 25 pounds per 1000 barrels. In terms of weight percentage, the additives can be present in gasoline in a general range of .00004 to .04 percent and a preferable range of .0004 to .01 percent. If the additive to gasoline comprises an unreacted mixture of-lecithin and ethoxylated or propoxylated triamine or tetramine, the components of the mixture can be preesnt over a wide ratio range. For example, the ratio of components in the mixture can range from substantially no lecithin to from about 1:100 to about 20:1 weight ratio of lecithin to amine.

The gasoline compositions of this invention contain as the hydrocarbon portion thereof any of the known gasoline hydrocarbons, such as, for example, hydrocarbons boiling between about 90 and 400 or 425 F. The hydrocarbon portion of the gasoline compositions can contain normal, branched-chain, and cyclic hydrocarbons having from 4 to 12 carbon atoms. The hydrocarbon portion of the gasoline compositions can comprise products prepared in the chemical conversion of hydrocarbons to produce gasoline such as the products prepared by isomerization, alkylation, polymerization, cracking, disproportionation, hydrogenation, dehydrogenation, and combinations of such processes. A common gasoline composition contains a major proportion of the gasoline hydrocarbons prepared by fluid catalytic cracking and a minor proportion of an alkylate prepared from isobutane and C and/or C olefins. The base fuel can comprise about 80 percent of gasoline from the fluid catalytic cracking process, and about 20 percent of the aforementioned alkylate.

EXAMPLE 1 A radioactive piston ring wear test was performed to demonstrate the high antiwear characteristics of a gasoline containing a compound of this invention. Following is a description of the procedure employed in the radioactive piston ring wear test.

Test procedure The radioactive ring wear test was performed with a laboratory test, 4-stroke, single cylinder internal combustion engine equipped with a cast iron top compression ring which prior to use had been rendered radioactive by insertion into the pile of an atomic reactor. The engine provided with the radioactive ring was operated at constant speed for 10 hours under the following test conditions:

Speed: r.p.m. 2000.

Load: BHP 5.

Spark 15 before top center. Air-fuel ratio 13.7/1.0.

Cylinder wall temp. F. 112.

Sump oil temp. F. 125.

Carburetor: intake air temp. F. 85.

During the test the motor oil accumulated particles of the radioactive metal lost by the radioactive piston ring through year. The radioactive metal content of the motor oil was continuously counted by means of a Geiger counter and recorded. At intervals oil samples were taken and the amount of dilution of oil by fuel was determined. Since dilution of oil by fuel tends to depress the radioactivity measurement, the amount of wear was calculated on the basis of radioactivity counts corrected by a factor corresponding to amount of dilution of the motor oil with fuel.

Table 1 shows the result of the radioactive piston ring wear test.

TABLE l.-RADIOACTIVE PISTON RING WEAR TEST Percent change As shown in Table 1, the antiwear agent of this invention reduced the piston ring wear rate 15 percent as compared to a reference gasoline.

EXAMPLE 2 Tests were conducted to illustrate the improvement imparted to gasoline by lecithin mixtures with an ethoxylated triamine of this invention and by lecithin derivatives of an ethoxylated triamine of this invention in regard to (1) reducing the tendency of gasoline to clog a fuel filter element and in regard to (2) performance of a carburetor gum detergency function to inhibit formation of or remove gummy carburetor deposits. In order to illustrate the especially high utility of the lecithin derivatives of this invention in regard to reduction of carburetor-type gum deposits, comparative tests were also conducted employing lecithin mixtures with and reaction products of closely related compounds. The results of these tests are presented in Table 2.

TABLE 2 Gasoline additives:

Lecithin X Reaction product of lecithin and the X reaction product of long chain fatty acids and diethylene triamine Mixture of lecithin and the reaction X product of long chain fatty acids and diethylene triamine Reaction product of lecithin and the X reaction product of long chain fatty acids and dipropylene triamine plus 2 mols of ethylene oxide Mixture of lecithin and the reaction X product of long chain fatty acids and dipropylene triamine plus 2 mols of ethylene oxide Reaction product of lecithin and the X the reaction product of dipropylene triamine and 2 mols of ethylene oxide Mixture of lecithin and the reaction X product of dipropylene triamine 2 mols of ethylene oxide Reaction product of lecithin plus X plus the reaction product of dipropylene triamine and 1 mol of ethylene oxide.

Mixture of lecithin plus the reaction X product of dipropylene triamine and 1 mol of ethylene oxide Gasoline tests:

Gasoline Circulation Test percent 50%, 10-15 20 22%, 20 20 20% 20 20 54%, 20 35%, 20 38%, 20

reduction in flow rate at stated fuel throughput in gallons (more than percent reduction in flow rate at 20 gallons fuel throughput is unsatisfactory), gals.

Intake System Deposit Test per- 46 48 61 58 59 20 49 83 33 cent reduction in carburetor-type gum deposits.

e A commercial neutral oil solution of a filtered soybean lecithin with moisture value less than 0.75 percent by weight, an acetone-insoluble value of 70 percent by weight and a viscosity of 3,046 centipoises.

b A commercial mixture comprising about 90 to 95 percent by weight of I-(Z-aminoethyl)-2-heptadecenylimidazoline; (C17)CNCH2CH2NH2 N CH2 0 2 c A mixture comprising in major proportion (C17)?NCH2CHNH(CH2CHQO)2H CH $11. and/or methyl isomers thereof, or corresponding imidazolines having two separate hydroxyethyl groups attached to the side chain nitrogen.

d Diethoxylated dipropylene triamine CH CH 4 NHz CHCH2NHCH2-CHNH(CH CH2O)2H and/or methyl isomers thereof, or corresponding triamines having two separate hydroxyethyl groups attached to a terminal nitrogen.

e Monoethoxylated dipropylene triamine NH2CH-CHzNHCH2CH-NHCHzCHzOH and/or methyl isomers thereof.

Ha CH3 1 For the Gasoline Circulation Tests additive concentrations were 15 lbs. per 1,000 barrels of gasoline plus 0.5 percent by volume solvent oil. Gasoline Circulation Test procedure is described in SAE Reprint N o. 610 B, G. E. Gaston and .T. J. Thomas, Contribution of Sediment and Additives in Gasoline to Clogging of Filters in Automotive Fuel Systems, presented at Philadelphia, Pa., Meetings, Oct. 29-Nov. 2, 1062.

e For the Intake System Deposit Tests the concentration of additives was 15 lbs. per 1,000 barrels of gasoline. The test simulates deposition of gum carried by gasoline in a carburetor and involves forming a gum deposit in a test apparatus by evaporating additiveeontaining, high gum content fuel flowing countercurrent to a stream of heated air. At the end of the test, the weight of the adhering gum is determined and compared to areferencerun without additive for an appraisal of the additives detergency action. The test employs the same apparatus described by J L. Keller and F. S. Liggett Induction System Gum-Engine Versus Bench Test, symposium on Vapor Phase Oxidation of Gasoline, ASTM Special Technical Publication No. 202, pp. 21-40 (1956), but a somewhat different procedure is employed in order to appraise detergency action of additives. A gum deposit is formed on the walls of a steam-jacketed glass U-tube by evaporating two liters of gasoline distillate admitted to the system, countercurrent to a stream of preheated air. The U-tube is then washed with a number of portions of naphtha until a final wash shows no discoloration. The amount of gum adhering to the apparatus is then determined by extracting with C. P. acetone and evaporating the acetone extract with filtered, heated air to obtain a gum residue which is heated in an oven for one-half hour at IOU-105 0., cooled and Weighed. Results of runs using the same gasoline with and without additives are compared to determine detergency action.

Table 2 shows that while lecithin alone reduced cardeparting from the spirit of this invention or the scope buretor-type gum deposits 46 percent, the reaction product thereof as defined in the following claims. of lecithin and dipropylene triamine plus 1 mol of ethyl- I claim: ene oxide produced an exceptional 83 percent reduction 60 1. A lecithin derivative of a compound having the forin carburetor-type gum deposits. Table 2 also shows that mula none of the other lecithin derivatives or mixtures tested were capable of imparting to gasoline a comparable ability R1 to reduce carburetor-type gum deposits. F '1 It is also shown in Table 2 that the gasoline sample conu I taining lecithin without amine showed unsatisfactory filter- Ra Ra clogging characteristics. The lecithin mixture with and the lecithin derivative of diethoxylated dipropylene triamine somewhat improved gasoline filter-clogging characteristics. However, the compounds of this invention which im- R R and R are selected from the group consisting of wherein proved gasoline most significantly in regard to filter-cloghydrogen, methyl and ethyl radicals,

ging characteristics were the lecithin mixture with and R and R are selected from the group consisting of ethyl the lecithin derivative of monoethoxylated dipropylene trione, trimethylene and propylene substituents,

amine. R is a -C H OH or C H OH substituent, and n is Various changes and modifications can be made without 1 or 2.

7 2. The lecithin derivative of dipropylene triamine eth- References Cited oxylate- UNITED STATES PATENTS 3. The lecrthm derivative of dipropylene trlamlne pro- 1 2,941,003 6/1960 Shokal 260563 poxy ate.

4. The lecithin derivative of a compound selected from 5 ELBERT ROBERTS, p i Examiner the group consisting of the ethoxylates and propoxylates of diethylene triamine, ditrimethylene triamine, triethylene tetramine, and tripropylene tetramine. 44 57, 72, 73; 260 584 

